Product Description:

Our 20mm Ballast is a pre-blended mix of sharp sand and 20mm gravel supplied in a bulk bag, ready to be combined with cement to make concrete. It is used for foundations and footings, shed and garage bases, concrete slabs, driveways and pathways, fence post setting, bedding kerbs and edgings, and general concreting across domestic and commercial projects.

Ballast takes the guesswork out of mixing concrete. Rather than buying sharp sand and aggregate separately and proportioning them on site, the two come ready blended in the correct ratio, so only cement and water need adding, and every batch comes out the same. The range of particle sizes is what gives concrete its strength: the gravel provides the bulk and the load-bearing structure, while the sand fills the spaces between the stones so the cured concrete is dense and solid rather than honeycombed with voids.

For most general concreting, a common mix is one part cement to five or six parts ballast, with a stronger one-to-four mix for structural work and foundations. Add clean water gradually and mix to a workable consistency, as excess water weakens the finished concrete considerably. Place and compact before it begins to set, and protect from frost and from drying too quickly in hot weather while it cures. Supplied in a bulk bag containing approximately 850kg, it is far more economical than handled bags for footings, bases, and anything beyond a small pour.